hitchcock



, naar sane @anni @Wire IENJAMIN. r. lIRVINE- AND THOMAS A. HITCHCOCK, OF NORTH 'IIA'CnOssH` WISCONSIN.

Letters Batent'No. 97,513, dated December 7,1869; antednted November 27, 1869.

IMPROVE-ZD ALARM-LOCK The Schedule referred to in these Lettera Patent and making part o f the came.

To all lwhom tt may concern.-

Be it known that we, BENJAMIN F. IRVINE and THOMAS A'. HITCHCOCK, of' North La Crosse, in `the ,countyof La Crosse, and State of lVisco'nsiu,

vhave invented a new and useful Improvement in Alarm-Locks; `and we do hereby declare that the fol lowing is a full and exact description of the same, reference being had to the `accompanying drawings, and to the letters of reference marked thereon.

` -This invention relates to an improved alarm-attach "ment forflocks, and consists mainly in certain devices, whereby the alarm can be` regulated to operate or re- Inainsilent when the lock-bolt is withdrawn, and, also, is readily adapted to a right or left-hand lock, as will. hereinafterlmore fully appear.

In theldrawings Figure 1 is a side elevation of nIy4 invention. Figure 2, a side elevation of my invention,'with the Vouter covering-plate removed.

'Figure 3` is a side elevation ofthe inner side ofthe 'outerplate vFigure 'f1' is a section through line x as; V

rIYo enable others skilled in the `art to make and use our invention, I will now, proceedi'to Vdescribe fully its construction andv operation.

A represents the lock-bolt, of the usual construction, provided with an enlarged head, on both ends, which pass through openin gs on each side of the casing.

On the upper part of the bolt A' is a slotted plate, B, secured by a setscrew,

The plate B vruns longitudinally with the bolt, and is 'provided at each end with the pins or 'projec- B represents the alarm-device,y whichfconsists of an ordinary clock-spring, attached to the shaft of the cog- .wheel O, and,i when wound up, imparts'r'notion there to, which is communicated to the escape-wheel o.

D is a' bent arm, which is attached to a collar, which C surrounds a post between the plates oi the alarm-device, and extends downward between the proiections c', on the plate B.

d represents a pawl, which is. rigidly attached to the collar, and, when the bolt is locked, holds the es- 'capementl `certain extent, and partially removes the pawl from the teeth of the escapement. The latter then rapidly revolves, each tooth striking the pawl, and imparting a rapid vibrator-y motion to the hammer, which strikes the bell at every motion, thus producinga continuons ringing sound, which varies in power, according to the -strength of the mechanism and-size of the bell.

To Operate the lock without the alarm, we provide the spring 14, attached to the inner side of the plate X,between which is a wedge-shaped piece, j, operated by a shank passing through a slot in said plate, and terminating in a thumbfpiece, fl.'

One 'end ot' the spring F is rigidly attached to a projection on the plate, while the other is free, and the i'ee end is provided with a pin, fz, which, when pressed inward by the wedge f, comesy in Contact' with the arm D, to which it bears the same relation. as the pins a. i

To change the lock from a right to a left-hand one,

the plate B is moved along untilthe other end of the slot comes in "Contact with the sensei-ew.

Having thus fully described our invention, What we claim as new, and desire to secure by Letters Patent, isv

The slotted plate B, with projections C a' arranged v to operate-in connection with the double bolt A, sub'- stantially as and for the purpose set forth.

G. A, WRIGHT. 

